The rationale of using mesenchymal stem cells in patients with COVID-19-related acute respiratory distress syndrome: What to expect

Investigating the effect of mesenchymal stem cells on the rate of clinical and pathological improvement of asthmatic lung in mouse model

Asthma is a pulmonary disease and its pathophysiology includes inflammation, obstruction, edema of the airways, and mucus secretions in the airways. Mesenchymal stem cells (MSCs) are self-renewal that use the therapeutic potential of these cells can be applied as treatments of asthma. In this study, the effect of Mesenchyme stem cells on asthma was investigated. MSCs were administrated for asthmatic mice and then, percentage of eosinophils in blood and bronchoalveolar lavage fluid (BALF), levels of interleukine (IL)-4 and Immunoglubolin (Ig)E were measured. Also histopathological study of lung tissue was done. MSCs administration could control percentage of eosinophils in blood and BALF, levels of IgE and IL-4, eosinophilic inflammation, mucin realizing and goblet cell hyper-plasia. Administration of MSCs as treatment of asthma can be a useful and applicable therapy in control of asthma symptoms.

Mesenchymal stem cells prevent H7N9 virus infection via rejuvenating immune environment to inhibit immune-overactivity

BACKGROUND

Influenza is a clinically important infectious disease with a high fatality rate, which always results in severe pneumonia. Mesenchymal stem cells (MSCs) exhibit promising therapeutic effects on severe viral pneumonia, but whether MSCs prevent virus infection and contribute to the prevention of influenza remains unknown.

METHODS

ICR mice were pretreated with human umbilical cord (hUC) MSCs and then infected with the influenza H7N9 virus. Weight, survival days, and lung index of mice were recorded. Serum antibody against influenza H7N9 virus was detected according to the hemagglutination inhibition method. Before and after virus infection, T cell and B cell subtypes in the peripheral blood of mice were evaluated by flow cytometry. Cytokines in the supernatants of MSCs, innate immune cells, and mouse broncho alveolar lavage fluid (BALF) were determined by enzyme-linked immunosorbent assay (ELISA) or Luminex Assay.

RESULTS

Pretreatment with MSCs protected mice against influenza H7N9 virus infection. Weight loss, survival rate, and structural and functional damage to the lungs of infected mice were significantly improved. Mechanistically, MSCs modulated T lymphocyte response in virus-infected mice and inhibited the cGAS/STING pathway. Importantly, the protective effect of MSCs was mediated by cell-to-cell communications and attenuation of cytokine storm caused by immune overactivation.

Clinical Trials of Mesenchymal Stem Cells for the Treatment of COVID 19

Mesenchymal Stem Cells (MSCs) are being investigated as a treatment for a novel viral disease owing to their immunomodulatory, anti-inflammatory, tissue repair and regeneration characteristics, however, the exact processes are unknown. MSC therapy was found to be effective in lowering immune system overactivation and increasing endogenous healing after SARS-CoV-2 infection by improving the pulmonary microenvironment. Many studies on mesenchymal stem cells have been undertaken concurrently, and we may help speed up the effectiveness of these studies by collecting and statistically analyzing data from them. Based on clinical trial information found on clinicaltrials. gov and on 16 November 2020, which includes 63 clinical trials in the field of patient treatment with COVID-19 using MSCs, according to the trend of increasing studies in this field, and with the help of meta-analysis studies, it is possible to hope that the promise of MSCs will one day be realized. The potential therapeutic applications of MSCs for COVID-19 are investigated in this study.

Effectiveness of RCTs Pooling Evidence on Mesenchymal Stem Cell (MSC) Therapeutic Applications During COVID-19 Epidemic: A Systematic Review

Background

Global pandemic identified as coronavirus disease 2019 (COVID-19) has resulted in a variety of clinical symptoms, from asymptomatic carriers to those with severe acute respiratory distress syndrome (SARS) and moderate upper respiratory tract symptoms (URTS). This systematic review aimed to determine effectiveness of stem cell (SC) applications among COVID-19 patients.

Methods

Multiple databases of PubMed, EMBASE, Science Direct, Google Scholar, Scopus, Web of Science, and Cochrane Library were used. Studies were screened, chosen, and included in this systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 flowchart diagram and PRISMA checklist. Included studies' quality was assessed employing Critical Appraisal Skills Programme (CASP) quality evaluation criteria for 14 randomized controlled trials (RCTs).

Results

Fourteen RCTs were performed between the years of 2020 to 2022, respectively, with a sample size n = 574 (treatment group (n = 318); control group (n = 256)) in multiple countries of Indonesia, Iran, Brazil, Turkey, China, Florida, UK, and France. The greatest sample size reported from China among 100 COVID-19 patients, while the lowest sample of 9 COVID-19 patients from Jakarta, Indonesia, and the patient's age ranges from 18 to 69 years. Studies applied to the type of SC were "Umbilical cord MSCs, MSCs secretome, MSCs, Placenta-derived MSCs, Human immature dental pulp SC, DW-MSC infusion, Wharton Jelly-derived MSCs". The injected therapeutic dose was 1 × 10⁶ cells/kg, 1 × 10⁷ cells/kg, 1 × 10⁵ cells/kg, and 1 million cells/kg as per the evidence from the different studies. Studies focused on demographic variables, clinical symptoms, laboratory tests, Comorbidities, respiratory measures, concomitant therapies, Sequential Organ Failure Assessment score, mechanical ventilation, body mass index, adverse events, inflammatory markers, and PaO₂/FiO₂ ratio were all recorded as study characteristics.

Conclusion

Clinical evidence on MSC's therapeutic applications during COVID-19 pandemic has proven to be a promising therapy for COVID-19 patient recovery with no consequences and applied as a routine treatment for challenging ailments.

Human Umbilical Cord Mesenchymal Stem Cells Attenuate Severe Burn-Induced Multiple Organ Injury via Potentiating IGF-1 and BCL-2/BAX Pathway

Background

Early multiple organ injuries induced by severe burn predict a high mortality. Mesenchymal stem cells (MSCs) are able to repair and reconstruct the injured tissues and organs induced by trauma and diseases. However, potential protective effect and mechanism of MSCs on multiorgan injury induced by severe burn at early stage remain to be not clarified. Therefore, this study was to explore the effect and mechanism of human umbilical cord-derived MSCs (hUCMSCs) against severe burn-induced early organ injuries in rats.

Methods

Adult male Wistar rats were randomly divided into sham, burn, and burn+hUCMSCsgroups. GFP-labeled hUCMSCs or PBS was intravenous injected into respective groups. Migration and distribution patterns of GFP-labeled hUCMSCs were observed by inverted fluorescence microscope. The structures and cell apoptosis of the heart, kidney, and liver were measured by immunohistochemistry. Biochemical parameters in serum were assayed by standard Roche-Hitachi methodology. Western blotting was performed on these organs of rats in the three groups to explore the underlying mechanisms.

Results

At 24 hours after hUCMSCs transplantation, we found that GFP-labeled hUCMSCs mainly localized in the blood vessel of the heart, kidney, and liver and a very few cells migrated into tissues of these organs. Compared with the sham group, structure damages and cell apoptosis of these organs were induced by severe burn, and systematic administrations of hUCMSCs significantly improved the damaged structures, cell apoptosis rates, and biochemical parameters of these organs. Furthermore, IGF-1 (insulin-like growth factor 1) level in burn+hUCMSCs group was significantly higher than that in the sham and burn groups. Meanwhile, severe burn induced BCL-2/BAX significantly decreased compared to the sham group, and it was markedly increased by hUCMSCs administration.

Conclusion

The hUCMSCs transplantation can attenuate severe burn-induced early organ injuries and protect multiorgan functions by encouraging migration of hUCMSCs with blood circulation and increasing protective cytokine IGF-1 level and regulating BCL-2/BAX pathway of these vital organs. Furthermore, these data might provide the theoretical foundation for further clinical applications of hUCMSCs in burn areas.

Dimethyl sulfoxide-free cryopreservation solution containing trehalose, dextran 40, and propylene glycol for therapy with human adipose tissue-derived mesenchymal stromal cells

We evaluated a dimethyl sulfoxide (Me2SO)-free cryopreservation solution to freeze human adipose-derived mesenchymal stromal cells (hADSCs). In the first experiment, we compared the combined effects of 3% trehalose (3 T) and 5% dextran (5D) in lactated Ringer’s solution (LR) as a cryopreservation base solution containing 10% propylene glycol (PG). The cell viability of hADSCs immediately after thawing was significantly higher (p < 0.05) in LR supplemented with 3 T (LR-3 T) and with 3 T and 5D (LR-3 T-5D) than in LR. In the second experiment, we compared the cell characteristics of hADSCs freeze-thawed in LR-3 T-5D containing either 10% Me2SO or 10% PG. The cell viability, annexin V-positive ratio, colony-forming capacity, cell proliferation, cell surface antigen positivity, adipogenic differentiation, osteogenic differentiation, and genetic response to cytokine stimulation of hADSCs immediately after thawing were similar between the LR-3 T-5D containing 10% Me2SO and 10% PG. In the third experiment, we examined various concentrations of PG on the cell proliferative capacity of freeze-thawed hADSCs. The cell proliferative capacity of hADSCs frozen with LR-3 T-5D containing 2.5% to 5% PG was significantly higher (p < 0.05) than LR-3 T-5D containing 10% PG. Furthermore, the cell proliferative capacity of hADSCs frozen with LR-3 T-5D containing 4% PG was similar to that of fresh hADSCs. These results indicate that the combination of 3 T-5D in an LR solution as a basic solution is effective for post-thaw cell viability, and that the optimal concentration of PG to maintain the cell characteristics of hADSCs frozen with LR-3 T-5D is 2.5% to 5%, which is promising for cell therapy applications.

A narrative review of COVID-19-related acute respiratory distress syndrome (CARDS): "typical" or "atypical" ARDS?

Background and Objective

The coronavirus disease of 2019 (COVID-19) is highly infectious and mainly involves the respiratory system, with some patients rapidly progress to acute respiratory distress syndrome (ARDS), which is the leading cause of death in COVID-19 patients. Hence, fully understanding the features of COVID-19-related ARDS (CARDS) and early management of this disease would improve the prognosis and reduce the mortality of severe COVID-19. With the development of recent studies which have focused on CARDS, whether CARDS is "typical" or "atypical" ARDS has become a hotly debated topic.

Methods

We searched for relevant literature from 1999 to 2021 published in PubMed by using the following keywords and their combinations: "COVID-19", "CARDS", "ARDS", "pathophysiological mechanism", "clinical manifestations", "prognosis", and "clinical trials". Then, we analyzed, compared and highlighted the differences between classic ARDS and CARDS from all of the aspects above.

Key Content and Findings

Classical ARDS commonly occurs within 1 week after a predisposing cause, yet the median time from symptoms onset to CARDS is longer than that of classical ARDS, manifesting within a period of 9.0-12.0 days. Although the lung mechanics exhibited in CARDS grossly match those of classical ARDS, there are some atypical manifestations of CARDS: the severity of hypoxemia seemed not to be proportional to injury of lung mechanics and an increase of thrombogenic processes. Meanwhile, some patients' symptoms do not correspond with the extent of the organic injury: a chest computed tomography (CT) will reveal the severe and diffuse lung injuries, yet the clinical presentations of patients can be mild.

Conclusions

Despite the differences between the CARDS and ARDS, in addition to the treatment of antivirals, clinicians should continue to follow the accepted evidence-based framework for managing all ARDS cases, including CARDS.

Human Placental Mesenchymal Stem Cells for the Treatment of ARDS in Rat

The acute respiratory distress syndrome (ARDS) is one of the main causes of high mortality in patients with coronavirus (COVID-19). In recent years, due to the coronavirus pandemic, the number of patients with ARDS has increased significantly. Unfortunately, until now, there are no effective treatments for ARDS caused by COVID-19. Many drugs are either ineffective or have a low effect. Currently, there have been reports of efficient use of mesenchymal stem cells (MSCs) for the treatment of ARDS caused by COVID-19. We investigated the influence of freeze-dried human placenta-derived mesenchymal stem cells (HPMSCs) in ARDS rat model. All animals have received intratracheal injection of 6 mg/kg of lipopolysaccharide (LPS). The rats were randomly divided into five groups: I: LPS, II: LPS+dexamethasone, III: LPS+HPMSCs, IV: HPMSC, and V: saline. ARDS observation time was short-term and amounted to 168 hours. The study has shown that HPMSCs are able to migrate and attach to damaged lung tissue, contributing to the resolution of pathology, restoration of function, and tissue repair in the alveolar space. Studies have also shown that the administration of HPMSCs in animals with ARDS model significantly reduced the levels of key cytokines such as IL-1β, IL-6, and TNF-α. Freeze-dried placental stem cell is a very promising biomaterial for the treatment of ARDS. The human placenta can be easily obtained because it is considered as a medical waste. At the same time, a huge number of MSCs can be obtained from the placental tissue, and there is no ethical controversy around their use. The freeze-dried MSCs from human placental tissue can be stored sterile at room temperature for a long time before use.

Human gingival mesenchymal stem cells retain their growth and immunomodulatory characteristics independent of donor age

Aging has been reported to deteriorate the quantity and quality of mesenchymal stem cells (MSCs), which affect their therapeutic use in regenerative medicine. A dearth of age-related stem cell research further restricts their clinical applications. The present study explores the possibility of using MSCs derived from human gingival tissues (GMSCs) for studying their ex vivo growth characteristics and differentiation potential with respect to donor age. GMSCs displayed decreased in vitro adipogenesis and in vitro and in vivo osteogenesis with age, but in vitro neurogenesis remained unaffected. An increased expression of p53 and SIRT1 with donor age was correlated to their ability of eliminating tumorigenic events through apoptosis or autophagy, respectively. Irrespective of donor age, GMSCs displayed effective immunoregulation and regenerative potential in a mouse model of LPS-induced acute lung injury. Thus, we suggest the potential of GMSCs for designing cell-based immunomodulatory therapeutic approaches and their further extrapolation for acute inflammatory conditions such as acute respiratory distress syndrome and COVID-19.

Case series of the first three severe COVID-19 patients treated with the secretome of hypoxia-mesenchymal stem cells in Indonesia

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the outbreak of coronavirus disease 2019 (COVID-19), which has been rapidly spreading. Several guideline therapies have been proposed as a possible treatment for SARS-CoV-2, however, these therapies are not sufficient to treat a severe condition of SARS-CoV-2 infection characterised by the increase of D-dimer and C-reactive protein (CRP) levels, and patchy ground-glass opacities (GGOs). Secretome-mesenchymal stem cells (S-MSCs) produced by MSCs under hypoxia could excessively release several anti-inflammatory cytokines and growth factors to control the COVID-19 cytokine storm and accelerate lung injury improvement. This is the first study investigating the clinical outcomes of three severe COVID-19 patients admitted to the intensive care unit of three different hospitals in Indonesia treated with S-MSCs. The decrease of D-dimer and CRP level was reported for all patients treated with S-MSCs. This was in line with improvement of pulmonary radiology, blood gas level, and hematologic assessment. In conclusion, these cases suggest that S-MSCs could effectively control D-dimer, CRP level and GGOs of severe COVID-19 patients associated with recovered pulmonary function.

Cellular therapies for the treatment and prevention of SARS-CoV-2 infection

Patients with blood disorders who are immune suppressed are at increased risk for infection with severe acute respiratory syndrome coronavirus 2. Sequelae of infection can include severe respiratory disease and/or prolonged duration of viral shedding. Cellular therapies may protect these vulnerable patients by providing antiviral cellular immunity and/or immune modulation. In this recent review of the field, phase 1/2 trials evaluating adoptive cellular therapies with virus-specific T cells or natural killer cells are described along with trials evaluating the safety, feasibility, and preliminary efficacy of immune modulating cellular therapies including regulatory T cells and mesenchymal stromal cells. In addition, the immunologic basis for these therapies is discussed.

Stem cell therapy for COVID-19 pneumonia

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus is a highly contagious microorganism, and despite substantial investigation, no progress has been achieved in treating post-COVID complications. However, the virus has made various mutations and has spread around the world. Researchers have tried different treatments to reduce the side effects of the COVID-19 symptoms. One of the most common and effective treatments now used is steroid therapy to reduce the complications of this disease. Long-term steroid therapy for chronic inflammation following COVID-19 is harmful and increases the risk of secondary infection, and effective treatment remains challenging owing to fibrosis and severe inflammation and infection. Sometimes our immune system can severely damage ourselves in disease. In the past, many researchers have conducted various studies on the immunomodulatory properties of stem cells. This property of stem cells led them to modulate the immune system of autoimmune diseases like diabetes, multiple sclerosis, and Parkinson's. Because of their immunomodulatory properties, stem cell-based therapy employing mesenchymal or hematopoietic stem cells may be a viable alternative treatment option in some patients. By priming the immune system and providing cytokines, chemokines, and growth factors, stem cells can be employed to build a long-term regenerative and protective response. This review addresses the latest trends and rapid progress in stem cell treatment for Acute Respiratory Distress Syndrome (ARDS) following COVID-19.

Purinergic signaling elements are correlated with coagulation players in peripheral blood and leukocyte samples from COVID-19 patients

For over a year, the coronavirus disease 2019 has been affecting the world population by causing severe tissue injuries and death in infected people. Adenosine triphosphate (ATP) and the nicotinamide adenine dinucleotide (NAD +) are two molecules that are released into the extracellular microenvironment after direct virus infection or cell death caused by hyper inflammation and coagulopathy. Also, these molecules are well known to participate in multiple pathways and have a pivotal role in the purinergic signaling pathway. Thus, using public datasets available on the Gene Expression Omnibus (GEO), we analyzed raw proteomics data acquired using mass spectrometry (the gold standard method) and raw genomics data from COVID-19 patient samples obtained by microarray. The data was analyzed using bioinformatics and statistical methods according to our objectives. Here, we compared the purinergic profile of the total leukocyte population and evaluated the levels of these soluble biomolecules in the blood, and their correlation with coagulation components in COVID-19 patients, in comparison to healthy people or non-COVID-19 patients. The blood metabolite analysis showed a stage-dependent inosine increase in COVID-19 patients, while the nucleotides ATP and ADP had positive correlations with fibrinogen and other coagulation proteins. Also, ATP, ADP, inosine, and hypoxanthine had positive and negative correlations with clinical features. Regarding leukocyte gene expression, COVID-19 patients showed an upregulation of the P2RX1, P2RX4, P2RX5, P2RX7, P2RY1, P2RY12, PANX1, ADORA2B, NLPR3, and F3 genes. Yet, the ectoenzymes of the canonical and non-canonical adenosinergic pathway (ENTPD1 and CD38) are upregulated, suggesting that adenosine is produced by both active adenosinergic pathways. Hence, approaches targeting these biomolecules or their specific purinoreceptors and ectoenzymes may attenuate the high inflammatory state and the coagulopathy seen in COVID-19 patients. KEY MESSAGES : Adenosinergic pathways are modulated on leukocytes from COVID-19 patients. Plasmatic inosine levels are increased in COVID-19 patients. ATP, ADP, AMP, hypoxanthine, and inosine are correlated with coagulation players. The nucleotides and nucleosides are correlated with patients' clinical features. The P2 receptors and ectoenzymes are correlated with Tissue factor in COVID-19.

The critical role of mesenchymal stromal/stem cell therapy in COVID-19 patients: An updated review

New coronavirus disease 2019 (COVID-19), as a pandemic disaster, has drawn the attention of researchers in various fields to discover suitable therapeutic approaches for the management of COVID-19 patients. Currently, there are many worries about the rapid spread of COVID-19; there is no approved treatment for this infectious disease, despite many efforts to develop therapeutic procedures for COVID-19. Emerging evidence shows that mesenchymal stromal/stem cell (MSC) therapy can be a suitable option for the management of COVID-19. These cells have many biological features (including the potential of differentiation, high safety and effectiveness, secretion of trophic factors and immunoregulatory features) that make them suitable for the treatment of various diseases. However, some studies have questioned the positive role of MSC therapy in the treatment of COVID-19. Accordingly, in this paper, we will focus on the therapeutic impacts of MSCs and their critical role in cytokine storm of COVID-19 patients.

SARS-CoV-2: Current trends in emerging variants, pathogenesis, immune responses, potential therapeutic, and vaccine development strategies

More than a year after the SARS-CoV-2 pandemic, the Coronavirus disease 19 (COVID-19) is still a major global challenge for scientists to understand the different dimensions of infection and find ways to prevent, treat, and develop a vaccine. On January 30, 2020, the world health organization (WHO) officially announced this new virus as an international health emergency. While many biological and mechanisms of pathogenicity of this virus are still unclear, it seems that cytokine storm resulting from an immune response against the virus is considered the main culprit of the severity of the disease. Despite many global efforts to control the SARS-CoV-2, several problems and challenges have been posed in controlling the COVID-19 infection. These problems include the various mutations, the emergence of variants with high transmissibility, the short period of immunity against the virus, the possibility of reinfection in people improved, lack of specific drugs, and problems in the development of highly sensitive and specific vaccines. In this review, we summarized the results of the current trend and the latest research studies on the characteristics of the structure and genome of the SARS-CoV- 2, new mutations and variants of SARS-CoV-2, pathogenicity, immune response, virus diagnostic tests, potential treatment, and vaccine candidate.

The Potential of Mesenchymal Stem Cells for the Treatment of Cytokine Storm due to COVID-19

The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has seriously affected public health and social stability. The main route of the transmission is droplet transmission, where the oral cavity is the most important entry point to the body. Due to both the direct harmful effects of SARS-CoV-2 and disordered immune responses, some COVID-19 patients may progress to acute respiratory distress syndrome or even multiple organ failure. Genetic variants of SARS-CoV-2 have been emerging and circulating around the world. Currently, there is no internationally approved precise treatment for COVID-19. Mesenchymal stem cells (MSCs) can traffic and migrate towards the affected tissue, regulate both the innate and acquired immune systems, and participate in the process of healing. Here, we will discuss and investigate the mechanisms of immune disorder in COVID-19 and the therapeutic activity of MSCs, in particular human gingiva mesenchymal stem cells.

The Potential Contribution of Biopolymeric Particles in Lung Tissue Regeneration of COVID-19 Patients

The lung is a vital organ that houses the alveoli, which is where gas exchange takes place. The COVID-19 illness attacks lung cells directly, creating significant inflammation and resulting in their inability to function. To return to the nature of their job, it may be essential to rejuvenate the afflicted lung cells. This is difficult because lung cells need a long time to rebuild and resume their function. Biopolymeric particles are the most effective means to transfer developing treatments to airway epithelial cells and then regenerate infected lung cells, which is one of the most significant symptoms connected with COVID-19. Delivering biocompatible and degradable natural biological materials, chemotherapeutic drugs, vaccines, proteins, antibodies, nucleic acids, and diagnostic agents are all examples of these molecules' usage. Furthermore, they are created by using several structural components, which allows them to effectively connect with these cells. We highlight their most recent uses in lung tissue regeneration in this review. These particles are classified into three groups: biopolymeric nanoparticles, biopolymeric stem cell materials, and biopolymeric scaffolds. The techniques and processes for regenerating lung tissue will be thoroughly explored.

SARS-CoV-2 Exposed Mesenchymal Stromal Cell from Congenital Pulmonary Airway Malformations: Transcriptomic Analysis and the Expression of Immunomodulatory Genes

The inflammatory response plays a central role in the complications of congenital pulmonary airway malformations (CPAM) and severe coronavirus disease 2019 (COVID-19). The aim of this study was to evaluate the transcriptional changes induced by SARS-CoV-2 exposure in pediatric MSCs derived from pediatric lung (MSCs-lung) and CPAM tissues (MSCs-CPAM) in order to elucidate potential pathways involved in SARS-CoV-2 infection in a condition of exacerbated inflammatory response. MSCs-lung and MSCs-CPAM do not express angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TRMPSS2). SARS-CoV-2 appears to be unable to replicate in MSCs-CPAM and MSCs-lung. MSCs-lung and MSCs-CPAM maintained the expression of stemness markers MSCs-lung show an inflammatory response (IL6, IL1B, CXCL8, and CXCL10), and the activation of Notch3 non-canonical pathway; this route appears silent in MSCs-CPAM, and cytokine genes expression is reduced. Decreased value of p21 in MSCs-lung suggested no cell cycle block, and cells did not undergo apoptosis. MSCs-lung appears to increase genes associated with immunomodulatory function but could contribute to inflammation, while MSCs-CPAM keeps stable or reduce the immunomodulatory receptors expression, but they also reduce their cytokines expression. These data indicated that, independently from their perilesional or cystic origin, the MSCs populations already present in a patient affected with CPAM are not permissive for SARS-CoV-2 entry, and they will not spread the disease in case of infection. Moreover, these MSCs will not undergo apoptosis when they come in contact with SARS-CoV-2; on the contrary, they maintain their staminality profile.

Case series of the first three severe COVID-19 patients treated with the secretome of hypoxia-mesenchymal stem cells in Indonesia

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the outbreak of coronavirus disease 2019 (COVID-19), which has been rapidly spreading. Several guideline therapies have been proposed as a possible treatment for SARS-CoV-2, however, these therapies are not sufficient to treat a severe condition of SARS-CoV-2 infection characterised by the increase of D-dimer and C-reactive protein (CRP) levels, and patchy ground-glass opacities (GGOs). Secretome-mesenchymal stem cells (S-MSCs) produced by MSCs under hypoxia could excessively release several anti-inflammatory cytokines and growth factors to control the COVID-19 cytokine storm and accelerate lung injury improvement. This is the first study investigating the clinical outcomes of three severe COVID-19 patients admitted to the intensive care unit of three different hospitals in Indonesia treated with S-MSCs. The decrease of D-dimer and CRP level was reported for all patients treated with S-MSCs. This was in line with improvement of pulmonary radiology, blood gas level, and hematologic assessment. In conclusion, these cases suggest that S-MSCs could effectively control D-dimer, CRP level and GGOs of severe COVID-19 patients associated with recovered pulmonary function.

Mechanism of Anosmia Caused by Symptoms of COVID-19 and Emerging Treatments

The occurrence of anosmia, the loss or change in sense of smell, is one of the most common symptoms of COVID-19 experienced by almost 53% of those affected. Several hypotheses explain the mechanism of anosmia in patients suffering from COVID-19. This study aims to review the related mechanisms and answer the questions regarding COVID-19-related anosmia as well as propose a new strategy for treatment of long-term anosmia as a result of COVID-19 infection. This paper covers all of the studies investigating olfactory disorders following COVID-19 infection and explains the possible reasons for the correlated anosmia, including olfactory cleft syndrome, local inflammation in the nasal epithelium, early apoptosis of olfactory cells, changes in olfactory cilia and odor transmission, damage to microglial cells, effect on olfactory bulbs, epithelial olfactory injury, and impairment of olfactory neurons and stem cells. The key questions that arise in this field have been discussed, such as why prevalent anosmia is varied among the age categories and among sexes and the correlation of anosmia with mild or severe COVID-19 infection. The angiotensin-converting enzyme 2 receptor is a significant player in the mechanism of anosmia in COVID-19 patients. Based on current studies, a novel approach to treat long-COVID-19 with ongoing anosmia has been proposed. The fields of smart drug delivery, tissue engineering, and cell therapy provide a hypothesized strategy that can minimize the side effects of current treatments and support efficient recovery of the olfactory system.

Microencapsulated Wharton Jelly-derived adult mesenchymal stem cells as a potential new therapeutic tool for patients with COVID-19 disease: an in vitro study

BACKGROUND

The recent newly appeared Coronavirus disease (COVID-19), caused by an enveloped RNA virus named "severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)", is associated with severe respiratory morbidity and mortality. Recent studies have shown that lymphopenia and a cytokine mass release represent important pathogenic features, with clinical evidence of dyspnea and hypoxemia, often leading to acute respiratory distress syndrome (ARDS), in severely ill patients, with a high death toll. Currently, stem cells are actively being investigated for their potential use in many "untreatable" diseases. In this regard and in particular, Mesenchymal Stem Cells (MSC), due to their intrinsic features, including either ability to impact on regulation of the immune system, or association with both anti-viral and anti-inflammatory properties, or potential for differentiation into several cell lineages, have become a promising tool for cell and molecular-based therapies. On this background, we wished to explore whether human umbilical cord-derived mesenchymal stem cells (hUCMS) would represent a potential viable therapeutic approach for the management of critically ill COVID19 patients.

METHODS

We tested the hUCMS effects on peripheral blood mononuclear cell (PBMCs) retrieved from patients with COVID19 (Ethical Committee CEAS Umbria, Italy CER N°3658/20 7, May, 2020), both as free cell monolayers and after envelopment in sodium alginate microcapsules. Both cell systems, after priming with IFN-γ, proved able to produce several immunomodulatory molecules such as IDO1 and HLAG5, although only the microencapsulated hUCMS were associated with massive and dose-dependent production of these factors.

RESULTS

The microencapsulated hUCMS improved allo-suppression in mixed lymphocytes reactions (MLRs), while also blunting T helper 1 and T helper 17 responses, that are involved with the cytokine storm and greatly contribute to the patient death. Moreover, we observed that both free and microencapsulated hUCMS permitted 5 days survival of in vitro culture maintained PBMCs extracted from very ill patients.

CONCLUSION

We have provided evidence that microencapsulated hUCMS in vitro, seem to represent a powerful tool to impact on several immune pathways, clearly deranged in COVID19 patients. Further study is necessary to begin in vivo assessment of this experimental system, upon determining both, the most appropriate time of the disease onset for intervention, and cell dosage/patient of our experimental product.

Updates on clinical trials evaluating the regenerative potential of allogenic mesenchymal stem cells in COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected nearly 118 million people and caused ~2.6 million deaths worldwide by early 2021, during the coronavirus disease 2019 (COVID-19) pandemic. Although the majority of infected patients show mild-to-moderate symptoms, a small fraction of patients develops severe symptoms. Uncontrolled cytokine production and the lack of substantive adaptive immune response result in hypoxia, acute respiratory distress syndrome (ARDS), or multiple organ failure in severe COVID-19 patients. Since the current standard of care treatment is insufficient to alleviate severe COVID-19 symptoms, many clinics have been prompted to perform clinical trials involving the infusion of mesenchymal stem cells (MSCs) due to their immunomodulatory and therapeutic properties. Several phases I/II clinical trials involving the infusion of allogenic MSCs have been performed last year. The focus of this review is to critically evaluate the safety and efficacy outcomes of the most recent, placebo-controlled phase I/II clinical studies that enrolled a larger number of patients, in order to provide a statistically relevant and comprehensive understanding of MSC's therapeutic potential in severe COVID-19 patients. Clinical outcomes obtained from these studies clearly indicate that: (i) allogenic MSC infusion in COVID-19 patients with ARDS is safe and effective enough to decreases a set of inflammatory cytokines that may drive COVID-19 associated cytokine storm, and (ii) MSC infusion efficiently improves COVID-19 patient survival and reduces recovery time. These findings strongly support further investigation into MSC-infusion in larger clinical trials for COVID-19 patients with ARDS, who currently have a nearly 50% of mortality rate.

Umbilical cord mesenchymal stem cells for COVID-19 acute respiratory distress syndrome: A double-blind, phase 1/2a, randomized controlled trial

Acute respiratory distress syndrome (ARDS) in COVID-19 is associated with high mortality. Mesenchymal stem cells are known to exert immunomodulatory and anti-inflammatory effects and could yield beneficial effects in COVID-19 ARDS. The objective of this study was to determine safety and explore efficacy of umbilical cord mesenchymal stem cell (UC-MSC) infusions in subjects with COVID-19 ARDS. A double-blind, phase 1/2a, randomized, controlled trial was performed. Randomization and stratification by ARDS severity was used to foster balance among groups. All subjects were analyzed under intention to treat design. Twenty-four subjects were randomized 1:1 to either UC-MSC treatment (n = 12) or the control group (n = 12). Subjects in the UC-MSC treatment group received two intravenous infusions (at day 0 and 3) of 100 ± 20 × 106 UC-MSCs; controls received two infusions of vehicle solution. Both groups received best standard of care. Primary endpoint was safety (adverse events [AEs]) within 6 hours; cardiac arrest or death within 24 hours postinfusion). Secondary endpoints included patient survival at 31 days after the first infusion and time to recovery. No difference was observed between groups in infusion-associated AEs. No serious adverse events (SAEs) were observed related to UC-MSC infusions. UC-MSC infusions in COVID-19 ARDS were found to be safe. Inflammatory cytokines were significantly decreased in UC-MSC-treated subjects at day 6. Treatment was associated with significantly improved patient survival (91% vs 42%, P = .015), SAE-free survival (P = .008), and time to recovery (P = .03). UC-MSC infusions are safe and could be beneficial in treating subjects with COVID-19 ARDS.

Exploring the utility of extracellular vesicles in ameliorating viral infection-associated inflammation, cytokine storm and tissue damage

Extracellular vesicles (EVs) have emerged as potential mediators of intercellular communication. EVs are nano-sized, lipid membrane-bound vesicles that contains biological information in the form of proteins, metabolites and/or nucleic acids. EVs are key regulators of tissue repair mechanisms, such as in the context of lung injuries. Recent studies suggest that EVs have the ability to repair COVID19-associated acute lung damage. EVs hold great promise for therapeutic treatments, particularly in treating a potentially fatal autoimmune response and attenuate inflammation. They are known to boost lung immunity and are involved in the pathogenesis of various lung diseases, including viral infection. EV-based immunization technology has been proven to elicit robust immune responses in many models of infectious disease, including COVID-19. The field of EV research has tremendous potential in advancing our understanding about viral infection pathogenesis, and can be translated into anti-viral therapeutic strategies.

Case series of the first three severe COVID-19 patients treated with the secretome of hypoxia-mesenchymal stem cells in Indonesia

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the outbreak of coronavirus disease 2019 (COVID-19), which has been rapidly spreading. Several guideline therapies have been proposed as a possible treatment for SARS-CoV-2, however, these therapies are not sufficient to treat a severe condition of SARS-CoV-2 infection characterised by the increase of D-dimer and C-reactive protein (CRP) levels, and patchy ground-glass opacities (GGOs). Secretome-mesenchymal stem cells (S-MSCs) produced by MSCs under hypoxia could excessively release several anti-inflammatory cytokines and growth factors to control the COVID-19 cytokine storm and accelerate lung injury improvement. This is the first study investigating the clinical outcomes of three severe COVID-19 patients admitted to the intensive care unit of three different hospitals in Indonesia treated with S-MSCs. The decrease of D-dimer and CRP level was reported for all patients treated with S-MSCs. This was in line with improvement of pulmonary radiology, blood gas level, and hematologic assessment. In conclusion, these cases suggest that S-MSCs could effectively control D-dimer, CRP level and GGOs of severe COVID-19 patients associated with recovered pulmonary function.

Is There an Effect of Fetal Mesenchymal Stem Cells in the Mother-Fetus Dyad in COVID-19 Pregnancies and Vertical Transmission?

Because of the polysystemic nature of coronavirus disease 2019 (COVID-19), during the present pandemic, there have been serious concerns regarding pregnancy, vertical transmission, and intrapartum risk. The majority of pregnant patients with COVID-19 infection present with mild or asymptomatic course of the disease. Some cases were hospitalized, and few needed intensive care unit admission, or mechanical ventilation. There have also been scarce case reports where neonates required mechanical ventilation post COVID-19 pregnancies. Without approved therapies other than dexamethasone, advanced mesenchymal cell therapy is one immunomodulatory therapeutic approach that is currently explored and might hold great promise. We suggest that the circulating fetal stem cells might have an immune-protective effect to mothers and contribute to the often mild and even asymptomatic post-COVID-19 pregnancies. Thus, COVID-19 pregnancies come forth as a paradigm to be further and more comprehensively approached, to understand both the mechanism and action of circulating stem cells in immunoprotection and hypoxia in microcirculation.

Evaluation of the safety and efficacy of using human menstrual blood-derived mesenchymal stromal cells in treating severe and critically ill COVID-19 patients: An exploratory clinical trial

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in December 2019 and has subsequently spread worldwide. Currently, there is no effective method to cure COVID-19. Mesenchymal stromal cells (MSCs) may be able to effectively treat COVID-19, especially for severe and critical patients. Menstrual blood-derived MSCs have recently received much attention due to their superior proliferation ability and their lack of ethical problems. Forty-four patients were enrolled from January to April 2020 in a multicenter, open-label, nonrandomized, parallel-controlled exploratory trial. Twenty-six patients received allogeneic, menstrual blood-derived MSC therapy, and concomitant medications (experimental group), and 18 patients received only concomitant medications (control group). The experimental group was treated with three infusions totaling 9 × 107 MSCs, one infusion every other day. Primary and secondary endpoints related to safety and efficacy were assessed at various time points during the 1-month period following MSC infusion. Safety was measured using the frequency of treatment-related adverse events (AEs). Patients in the MSC group showed significantly lower mortality (7.69% died in the experimental group vs 33.33% in the control group; P = .048). There was a significant improvement in dyspnea while undergoing MSC infusion on days 1, 3, and 5. Additionally, SpO2 was significantly improved following MSC infusion, and chest imaging results were improved in the experimental group in the first month after MSC infusion. The incidence of most AEs did not differ between the groups. MSC-based therapy may serve as a promising alternative method for treating severe and critical COVID-19.

Mesenchymal Stem Cell-Derived Extracellular Vesicles Carrying miRNA as a Potential Multi Target Therapy to COVID-19: an In Silico Analysis

In the end of 2019 COVID-19 emerged as a new threat worldwide and this disease present impaired immune system, exacerbated production of inflammatory cytokines, and coagulation disturbs. Mesenchymal stem cell (MSC) derived extracellular vesicles (EVs) have emerged as a therapeutic option due to its intrinsic properties to alleviate inflammatory responses, capable to promote the restoring of injured tissue. EVs contain heterogeneous cargo, including active microRNAs, small noncoding sequences involved in post-transcriptional gene repression or degradation and can attach in multiple targets. This study investigated whether the MSC-EVs miRNA cargo has the capacity to modulate the exacerbated cytokines, cell death and coagulation disturbs present in severe COVID-19. Through bioinformatics analysis, four datasets of miRNA, using different stem cell tissue sources (bone marrow, umbilical cord and adipose tissue), and one dataset of mRNA (bone marrow) were analyzed. 58 miRNAs overlap in the four miRNA datasets analyzed. Sequentially, those miRNAs present in at least two datasets, were analyzed using miRWalk for the 3’UTR binding target mRNA. The result predicted 258 miRNAs for exacerbated cytokines and chemokines, 266 miRNAs for cell death genes and 148 miRNAs for coagulation cascades. Some miRNAs may simultaneously attenuate inflammatory agents, inhibit cell death genes and key factors of coagulation cascade, consequently preventing tissue damage and coagulation disturbs. Therefore, the MSC-derived EVs due to their heterogeneous cargo are a potential multitarget approach able to improve the survival rates of severe COVID-19 patients.

An overview of the use of biomaterials, nanotechnology, and stem cells for detection and treatment of COVID-19: towards a framework to address future global pandemics

A novel SARS-like coronavirus (severe acute respiratory syndrome-related coronavirus-2, SARS-CoV-2) outbreak has recently become a worldwide pandemic. Researchers from various disciplinary backgrounds (social to natural science, health and medicine, etc.) have studied different aspects of the pandemic. The current situation has revealed how the ongoing development of nanotechnology and nanomedicine can accelerate the fight against the novel viruses. A comprehensive solution to this and future pandemic outbreaks includes preventing the spread of the virus through anti-viral personal protective equipment (PPE) and anti-viral surfaces, plus efforts to encourage behavior to minimize risks. Studies of previously introduced anti-viral biomaterials and their optimization to fight against SARS-CoV-2 is the foundation of most of the recent progress. The identification of non-symptomatic patients and symptomatic patients is vital. Reviewing published research highlights the pivotal roles of nanotechnology and biomaterials in the development and efficiency of detection techniques, e.g., by applying nanotechnology and nanomedicine as part of the road map in the treatment of coronavirus disease 2019 (COVID-19) patients. In this review, we discuss efforts to deploy nanotechnology, biomaterials, and stem cells in each step of the fight against SARS-CoV-2, which may provide a framework for future efforts in combating global pandemics.

Exploring the multifocal therapeutic approaches in COVID-19: A ray of hope

The ongoing global pandemic of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is marked as one of the most challenging infectious diseases in the history of mankind with affliction of ~29,737,453 confirmed cases globally. Looking at the present scenario where there is a parallel increment in curve with time, there is an utmost emergency to discover a perennial solution to this life-threatening virus which has led the Human race in an unusual state of affair. The entire health care fraternity is engaged in endeavouring an ultimate way out to hit this pandemic but no such research made till now has been approved yet, to have the potential to bring an end to this fatal situation. Although a few possible treatment choices exist at the moment yet the requirement to search for a still better therapeutic option remains persistent. Global laboratories are working day and night in search for an effective vaccine, many are undergoing clinical trials but their commercialization is no less than a year away. The present review highlights the current potential therapies viz., vaccines, immunotherapies, convulsant plasma therapies, corticosteroids, antithrombotic, intravenous immunoglobulins, nocturnal oxygen therapy etc. that may prove beneficial in attenuating the pandemic situation. However, comparison and presentation of collective data on the therapeutic advancements in mitigating the pandemic situation needs further clinical investigations in order to prove boon to mankind.

The Role of MSC Therapy in Attenuating the Damaging Effects of the Cytokine Storm Induced by COVID-19 on the Heart and Cardiovascular System

The global pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19) has led to 47 m infected cases and 1. 2 m (2.6%) deaths. A hallmark of more severe cases of SARS-CoV-2 in patients with acute respiratory distress syndrome (ARDS) appears to be a virally-induced over-activation or unregulated response of the immune system, termed a "cytokine storm," featuring elevated levels of pro-inflammatory cytokines such as IL-2, IL-6, IL-7, IL-22, CXCL10, and TNFα. Whilst the lungs are the primary site of infection for SARS-CoV-2, in more severe cases its effects can be detected in multiple organ systems. Indeed, many COVID-19 positive patients develop cardiovascular complications, such as myocardial injury, myocarditis, cardiac arrhythmia, and thromboembolism, which are associated with higher mortality. Drug and cell therapies targeting immunosuppression have been suggested to help combat the cytokine storm. In particular, mesenchymal stromal cells (MSCs), owing to their powerful immunomodulatory ability, have shown promise in early clinical studies to avoid, prevent or attenuate the cytokine storm. In this review, we will discuss the mechanistic underpinnings of the cytokine storm on the cardiovascular system, and how MSCs potentially attenuate the damage caused by the cytokine storm induced by COVID-19. We will also address how MSC transplantation could alleviate the long-term complications seen in some COVID-19 patients, such as improving tissue repair and regeneration.

Coronavirus disease 2019: investigational therapies in the prevention and treatment of hyperinflammation

Introduction: The mortality of coronavirus disease 2019 (COVID-19) is frequently driven by an injurious immune response characterized by the development of acute respiratory distress syndrome (ARDS), endotheliitis, coagulopathy, and multi-organ failure. This spectrum of hyperinflammation in COVID-19 is commonly referred to as cytokine storm syndrome (CSS). Areas covered: Medline and Google Scholar were searched up until 15th of August 2020 for relevant literature. Evidence supports a role of dysregulated immune responses in the immunopathogenesis of severe COVID-19. CSS associated with SARS-CoV-2 shows similarities to the exuberant cytokine production in some patients with viral infection (e.g.SARS-CoV-1) and may be confused with other syndromes of hyperinflammation like the cytokine release syndrome (CRS) in CAR-T cell therapy. Interleukin (IL)-6, IL-8, and tumor necrosis factor-alpha have emerged as predictors of COVID-19 severity and in-hospital mortality. Expert opinion: Despite similarities, COVID-19-CSS appears to be distinct from HLH, MAS, and CRS, and the application of HLH diagnostic scores and criteria to COVID-19 is not supported by emerging data. While immunosuppressive therapy with glucocorticoids has shown a mortality benefit, cytokine inhibitors may hold promise as 'rescue therapies' in severe COVID-19. Given the arguably limited benefit in advanced disease, strategies to prevent the development of COVID-19-CSS are needed.

Stem cell therapy for COVID-19, ARDS and pulmonary fibrosis

Coronavirus disease 2019 (COVID-19) is an acute respiratory infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 mainly causes damage to the lung, as well as other organs and systems such as the hearts, the immune system and so on. Although the pathogenesis of COVID-19 has been fully elucidated, there is no specific therapy for the disease at present, and most treatments are limited to supportive care. Stem cell therapy may be a potential treatment for refractory and unmanageable pulmonary illnesses, which has shown some promising results in preclinical studies. In this review, we systematically summarize the pathogenic progression and potential mechanisms underlying stem cell therapy in COVID-19, and registered COVID-19 clinical trials. Of all the stem cell therapies touted for COVID-19 treatment, mesenchymal stem cells (MSCs) or MSC-like derivatives have been the most promising in preclinical studies and clinical trials so far. MSCs have been suggested to ameliorate the cytokine release syndrome (CRS) and protect alveolar epithelial cells by secreting many kinds of factors, demonstrating safety and possible efficacy in COVID-19 patients with acute respiratory distress syndrome (ARDS). However, considering the consistency and uniformity of stem cell quality cannot be quantified nor guaranteed at this point, more work remains to be done in the future.

The rationale of using mesenchymal stem cells in patients with COVID-19-related acute respiratory distress syndrome: What to expect

The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2)‐caused coronavirus disease 2019 (COVID‐19) pandemic has become a global health crisis with an extremely rapid progress resulting in thousands of patients who may develop acute respiratory distress syndrome (ARDS) requiring intensive care unit (ICU) treatment. So far, no specific antiviral therapeutic agent has been demonstrated to be effective for COVID‐19; therefore, the clinical management is largely supportive and depends on the patients' immune response leading to a cytokine storm followed by lung edema, dysfunction of air exchange, and ARDS, which could lead to multiorgan failure and death. Given that human mesenchymal stem cells (MSCs) from various tissue sources have revealed successful clinical outcomes in many immunocompromised disorders by inhibiting the overactivation of the immune system and promoting endogenous repair by improving the microenvironment, there is a growing demand for MSC infusions in patients with COVID‐19‐related ARDS in the ICU. In this review, we have documented the rationale and possible outcomes of compassionate use of MSCs, particularly in patients with SARS‐CoV‐2 infections, toward proving or disproving the efficacy of this approach in the near future. Many centers have registered and approved, and some already started, single‐case or phase I/II trials primarily aiming to rescue their critical patients when no other therapeutic approach responds. On the other hand, it is also very important to mention that there is a good deal of concern about clinics offering unproven stem cell treatments for COVID‐19. The reviewers and oversight bodies will be looking for a balanced but critical appraisal of current trials.